1. Field of the Invention
The present invention relates to a high voltage power supply. More particularly, the present invention relates to a high voltage power supply having a voltage multiplying circuit part, which is capable of generating a high voltage using a diode and a capacitor element having low rated voltage.
2. Description of the Related Art
Generally, a high voltage power supply (HVPS) is employed in devices such as a copier, laser printer, facsimile, and digital printer as a core part, which operates to instantly convert low voltage of 12–24V to high voltage of several hundreds volts (V), or to several thousand volts (kV) for use in temporarily inscribing images on a drum of the printer or copier.
A conventional high voltage power supply generally increases the number of turns of a secondary side of a voltage transformer to increase the output voltage value, and then outputs the high voltage to a developing unit (not shown) and any number of associated circuit elements. However, because the voltage increase at both ends of such an element, including a diode or capacitor, is in direct proportion to the increased number of turns of the secondary side of the voltage transformer, it becomes necessary to use an element of high electrical output rate. Unfortunately, the price of a capacitor or diode increases in proportion to the increase of the voltage rate, and therefore, the price of high voltage power supplies is usually high.
This is often the case in high-speed and high-quality laser printers or copiers, in which a power supply having elements of higher output voltage and current capacitance is required. Therefore, the price of the power supply increases, as does the price of the printers or copiers.
Accordingly, a need exists for a power supply which is capable of providing high output voltage with constant voltage current, while reducing the rated capacity of the elements, such as diode or capacitor elements within the supply.